This invention relates to a circuit-like conveying system whereby work pieces are moved to various treatment stations and more particularly to a system for moving the work pieces along a generally horizontal path in a discontinuous manner and vertically as required and to a related transfer or lift mechanism.
Conveyors for moving work pieces from place to place or to treatment stations are well known. One conveyor type moves work pieces from place to place in a continuous manner. Another type of conveyor moves the work pieces in a start/stop or discontinuous manner so that the work pieces can be treated (usually dipped) at various stations. Such treatment may include painting, plating, cleansing and the like. Conveyors of this type move the work piece along a horizontal path, then the work piece may be stopped, moved vertically downwardly at a given station so as to dip the work piece in a treatment tank, upwardly out of the tank and then back along the horizontal path. A transfer or lift mechanism, positioned at the end of the conveyor, is provided for moving the work piece from one path or conveyor line to another. Conveyors of this type may receive untreated pieces from a remote conveyor and deliver treated pieces to the remote conveyor.
In a circuit-like conveying system there is provided a first or lower horizontal conveyor line or path along which the pieces are moved, stopped, lowered, treated, raised and moved to the end of the line. At the end of the line the pieces exit the first horizontal conveyor, are retrieved and moved vertically upwardly or delivered to the entrance to a second or upper horizontal line which may be a drying oven or drying station. The pieces are moved horizontally along a second or drying line (usually in an opposite direction to the first conveyor) to the exit of the second line and may be returned to the remote conveyor and an untreated piece can be retrieved and delivered to the entrance for the first conveyor. This type of movement is seen in connection with plating machines and the like and generally defines a circuit. Machines of this type are known in the prior art but are believed to be complex and unreliable.
It is an object of this invention to provide an improved circuit-like conveying system of the type described above which is less complex and more reliable than machines of the prior art.
Systems of the type described herein include a transfer or lift station at the exit end of the first line for retrieving treated pieces and moving the pieces upwardly for delivery to the entrance to a second conveyor line for drying or the like. A transfer station at the exit end of the second line is provided for removing dried pieces and delivering them to a remote conveyor. The transfer station or lift can also retrieve untreated pieces from the remote conveyor and move or deliver them into the entrance end of the first treatment line. Transfer or lift mechanisms in the prior art tend to be complex, unreliable and not identical at the respective ends of the lines.
It is an object of this invention to provide improved transfer stations or lift mechanisms which are less complex, reliable and substantially identical so that one can be placed at the end of the treatment line or the drying line for the movement of work pieces.
With respect to the first conveyor, the work pieces are substantially equally spaced from one another and are moved downwardly as a group into treatment tanks, treated, moved upwardly as a group and then moved on to the next station for additional treatment.
It is an object of this invention to provide an improved system for moving the work pieces as a group a fixed distance, dipping them into a plurality of tanks for treatment, raising them and moving them on to the next station.
These and other objects of this invention will become apparent from the following description and appended claims.